This project is part of our new initiative to develop a comprehensive research and development program to meet the challenging demands of future transfusion services. The increasing threats of emerging and re-emerging diseases, the quickened progress in the field of gene and cell therapy, and the ever-changing biotechnology have transformed the transfusion services greatly. Our viral hepatitis research and development program is built on an infectious disease model. Our specific goals for investigating gene therapy as a therapeutic approach for human hepatitis C virus (HCV) infection and developing this approach as a model for chronic infectious diseases are to (1) establish a functionally measurable gene expression in hematopoietic cells, using a viral-mediated gene delivery system for HCV gene; (2) develop lineage-specific gene expression in hematopoietic cells of HCV genes; (3) demonstrate the efficacy of lineage-specific gene expression by functional assessment with cytotoxic T lymphocyte assays and tumor killing assays directed to HCV specific epitopes; and (4) establish lineage-specific gene expression as a therapeutic modality against chronic HCV infection.